GB716505A - Improvements in or relating to hydroforming process - Google Patents

Abstract

<PICT:0716505/IV (b)/1> Naphtha is hydroformed in the presence of a dense fluidized catalyst which is withdrawn from the reaction zone, stripped of entrained gases by means of a stripping gas, and regenerated by passing in countercurrent to an oxygen-containing regeneration gas in a series of superimposed regeneration zones, in the complete absence of steam, the said gas entering the final and lowermost zone at a high temperature and passing through preceding zones at progressively lower temperatures to the first and uppermost zone maintained at 850-1000 DEG F. and the stripped catalyst entering the said first zone and passing to said final zone, being maintained in a fluidized state in said zones by the regeneration gas, and hydrogen completely removed in said first zone and residual carbon in succeeding zones, the regenerated catalyst then being recycled to the reaction zone. Naphtha is fed by pipe 14 and nozzles 15, and catalyst in suspension in hydrogen-rich gas by line 17 to reactor 10 to give a dense, fluidized bed 18. A ported conduit 23 serves to take off catalyst which is stripped by a countercurrent of steam or inert gas from pipe 26. The stripped catalyst passes by line 33 to regenerator 35 having perforated plates 36-39 with downcomers for conveying solids to the next lower plate. Oxygen-containing regeneration gas passes upwards from pipe 40 at a velocity to maintain a dense, fluidized catalyst bed on each plate. Combustion gases leave at the top and, if desired, may be used as stripping gas in conduit 23. The regeneration zones are operated at progressively higher temperatures, e.g. 850-1000 DEG F. in the top zone, and 1200 DEG F. in the bottom. Fresh feed may pass through coils 42-44 arranged in the catalyst beds whereby it is preheated while recycle gas is similarly heated in coils 47-49 before passing to line 17 where it effects a reconditioning of the catalyst while carrying it to reactor 10. In starting up, catalyst is fed through line 17 by an air stream, and hot air fed by line 40 until the reactor and regenerator are filled. Standpipe 51 is now opened, and the reactor purged with inert gas. Oil or fuel gas is fed to the regenerator to heat the catalyst; and fuel-gas supplied for conveying catalyst from standpipe 51 to the reactor until the latter reaches 850 DEG F. when naphtha feed begins. Reaction conditions are 850-975 DEG F., 50-1000 p.s.i.g., and 0.15-1.5 lb./lb. catalyst/hour. The catalyst to oil ratio may be 0.5-3. Specification 590,882, [Group III], is referred to.ALSO:Naphtha is hydroformed in the presence of a dense fluidized catalyst which is withdrawn from the reaction zone, stripped of entrained gases by means of a stripping gas, and regenerated by passing in countercurrent to an oxygen-containing regeneration gas in a series of superimposed regeneration zones, in the complete absence of steam, the said gas entering the final and lower-most zone at a high temperature and passing through preceding zones at progressively lower temperatures to the first and uppermost zone maintained at 850-1000 DEG F., and the stripped catalyst entering the said first zone and passing to said final zone, being maintained in a fluidized state in said zones by the regeneration gas, and hydrogen completely removed in said first zone and residual carbon in succeeding zones, the regenerated catalyst then being recycled to the reaction zone. Naphtha is fed by pipe 14 and nozzles 15, and catalyst in suspension in hydrogen-rich gas by line 17 to reactor 10 to give a dense fluidized bed 18. A ported conduit 23 serves to take off catalyst which is stripped by a countercurrent of steam or inert gas from pipe 26. The stripped catalyst passes by line 33 to regenerator 35 having perforated plates 36-39 <PICT:0716505/III/1> with downcomers for conveying solids to the next lower plate. Oxygen-containing regeneration gas passes upwards from pipe 40 at a velocity to maintain a dense fluidized catalyst bed on each plate. Combustion gases leave at the top and, if desired, may be used as stripping gas in conduit 23. The regeneration zones are operated at progressively higher temperatures, e.g. 850-1000 DEG F. in the top zone, and 1200 DEG F. in the bottom. Fresh feed may pass through coils 42-44 arranged in the catalyst beds whereby it is preheated while recycle gas is similarly heated in coils 47-49 before passing to line 17 where it effects the reconditioning of the catalyst while carrying it to reactor 10. In starting up, catalyst is fed through line 17 by an air stream and hot air fed by line 40 until the reactor and regenerator are filled. Standpipe 51 is now opened, and the reactor purged with inert gas. Oil or fuel gas is fed to the regenerator to heat the catalyst, and fuel gas supplied for conveying catalyst from standpipe 51 to the reactor until the latter reaches 850 DEG F. when naphtha feed begins. Reaction conditions are 850-975 DEG F., 50-1000 p.s.i.g., and .15-1.5 lbs./lb. catalyst/hr. The catalyst to oil ratio may be 0.5-3. Specification 590,882 is referred to.